I want to license my Minecraft mod with WTFPL. However, I have a small section of code which I incorporated from other mod, licensed under GPL, in the first release of my mod.

In the recent version (see dev branch of my mod) I refactored and rewrote it from scratch. I also got permission (see README of my mod) from the author of the other mod to use his code.

In this situation, do I have a freedom over choosing which license I can choose, in this case WTFPL, or must I stick only to GPL compatible licenses?

I'm still going to give credit to the original author of the mod, but I'm unsure about my licensing situation and control over my code.

Thank you for attention!

closed as off-topic by Jörg W Mittag, Doc Brown, Bart van Ingen Schenau, gnat, Robert Harvey Nov 6 '16 at 18:29

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "Questions asking for legal advice or aid are off-topic here. You may be able to get help with understanding, applying, and complying with free and open licenses on Open Source. You may be able to get help with legal terms, concepts, language, and procedures on Law." – Jörg W Mittag, Doc Brown, Bart van Ingen Schenau, Robert Harvey
If this question can be reworded to fit the rules in the help center, please edit the question.

  • 1
    It depends what kind of permission you got. A permission to use that other code, or a permission to redistribute it (or a work derived from it) under a different license. Anyway, we cannot tell you, you have to talk to that other guy. – Doc Brown Nov 6 '16 at 8:00
  • Here's the screenshot of the permission request. I didn't asked him about the license switch, but I'm asking you, people, since I mentioned that I rewrote his code using completely different technique. By the way, I'm total noob in the licensing. – McHorse Nov 6 '16 at 8:06
  • You still have to ask him, telling about the license change. – Doc Brown Nov 6 '16 at 8:13

In principle if you copy one line from a GPL or LGPL and distribute it you will be guilty of copyright infringement unless your software is distributed under (L)GPL. This is why they are called viral licenses.

You have to get the original author to license the code to you under a more permissive license. If you know you want to use WTFPLC the easiest is to just ask him to license the code to you under that license, but BSD, MIT, or MPL could also work.

In general all contributors to a piece of GPL software have to agree to license it under a different license, so this excercise is more complicated when there are many contributors to the GPL software.

  • 3
    Just a note for OP: I wouldn't get my hopes up that someone who used the GPL would, nor even could, give permission to use a license as permissive as WTFPL. It's likely that the person licensing the code based their code on someone else's who licensed it as GPL.... – RubberDuck Nov 6 '16 at 11:05
  • "If you copy one line" - nothing can force to have the same license. You have the choice of using the license, or being accused of copyright infringement. You are free to figure out the chances of going to court, losing in court, and paying the price. If you copy one line that price would very low. For example if Microsoft discovered that some idiot copied one GPL licensed line of code into the Word source code, and the product has shipped, it would not become GPL licensed. – gnasher729 Nov 6 '16 at 14:57
  • Your opening statement is false. Not even in principle. It depends on a lot of factors, particularly how special / creative the line(s) are. Copying printf("Application Starting") is not considered creative work. – whatsisname Nov 6 '16 at 18:27
  • @gnasher729 you are right. I've specified it. – Esben Skov Pedersen Nov 6 '16 at 18:29
  • Thanks for the answer :) I asked the author for permission to relicense. He gave me permission, so my problem is solved. However, this is really saddening that (L)GPL is advertised as free license, forces users to license their software under (L)GPL. Anyway, what about contributions? So if I license my software under GPL, and somebody contributes and creates a class, he basically has copyright on this class? Therefore disabling me from switching to another license? What about MIT license or WTFPL, is it works this way too with contributions? – McHorse Nov 9 '16 at 8:26

Not the answer you're looking for? Browse other questions tagged or ask your own question.